1. Field of the Invention
The present invention relates to a production method for a pressure-sensitive adhesive composition.
2. Description of the Related Art
When a pressure-sensitive adhesive tape is attached to any one of the various adherends, the pressure-sensitive adhesive tape is required to be easily and strongly attached to a predetermined position of the adherend. Accordingly, the pressure-sensitive adhesive tape is required to bring together “attachment position correction workability” that enables the tape to be easily aligned by expression of good temporary attachment property and “reworkability” that enables the tape to be easily reattached in a balanced manner. Further, in recent years, the tape has started to be required to have “temperature-sensitive strong pressure-sensitive adhesiveness” that enables the tape to express strong temperature-sensitive pressure-sensitive adhesiveness so as to be applied to, for example, a small cell-related application or an electronic equipment application. A hot melt-type pressure-sensitive adhesive using a thermoplastic resin has been conventionally known as a pressure-sensitive adhesive having the “temperature-sensitive strong pressure-sensitive adhesiveness.” However, the hot melt-type pressure-sensitive adhesive cannot maintain its film shape without a base material and hence it is difficult to apply the adhesive to, for example, abase material-less double-coated tape.
A pressure-sensitive adhesive composition containing an acrylic copolymer and a polyurethane(meth)acrylate has been recently reported as a pressure-sensitive adhesive composition capable of expressing high blistering resistance under a high-temperature environment (Japanese Patent No. 4666715).
The pressure-sensitive adhesive composition reported in Japanese Patent No. 4666715 is obtained by: mixing the acrylic copolymer obtained by radical polymerization and the polyurethane(meth)acrylate obtained by thermal polymerization with an additive; and applying the mixture onto a base material.
The pressure-sensitive adhesive composition reported in Japanese Patent No. 4666715 can express high blistering resistance under a high-temperature environment to some extent, but involves the following problem. The composition cannot sufficiently express the “attachment position correction workability” that enables a pressure-sensitive adhesive tape containing the composition to be easily aligned by expression of good temporary attachment property, the “reworkability” that enables the tape to be easily reattached, and the “temperature-sensitive strong pressure-sensitive adhesiveness” that enables the tape to express strong temperature-sensitive pressure-sensitive adhesiveness.